Chromogenic materials may be formed into films or thin layers on suitable substrates, depending on the nature of the chromogenic material, and in some cases, its intended use. Some electrochromic materials may be coated or deposited on a glass substrate by sputter coating, chemical vapor deposition, or the like, while others may be dispersed into a pre-formed chamber. Some chromogenic systems may incorporate multiple functional layers for operation—separate chromogenic, electrolyte, electrode and ion-intercalating layers, for example. Such a multi-layered chromogenic system may be formed by sequential deposition of layers—the layers may be individually treated (e.g. dried, polymerized, cured or the like) before deposition of subsequent layers. For some configurations, prevention of mixing of adjacent layer components may be necessary, and removal of co-solvent or carrier solvents may be required before deposition of a subsequent layer. This may be made more difficult in continuous throughput systems, and increase the number of variables in the procedure.
Some chromogenic materials may be coated onto a moving web using roll coating, knife coating, extrusion or the like, forming a continuous sheet of the chromogenic material, which may be later cut to a desired shape
While sheet-formed switchable materials may be cut successfully, the unused (weed) portions represent a waste of switchable material. Additionally, the exposed, cut edges of the switchable materials may be adversely affected by exposure to the ambient environment loss of solvent phase, interaction of switchable material components with air/oxygen, for example.
Constructing a chamber with opposing substrates and a circumferential seal, and backfilling the chamber is one method used to introduce an electrochromic material into a device, but this necessitates fill port(s) and multiple steps of construction—the seal material is disposed and allowed to cure or set, before a sufficiently fluid electrochromic material is introduced. Such a device may be difficult or impossible to form or mold to a desired shape, thus the opposing substrates would need to be pre-shaped, adding further complexity to the manufacturing process.